Characterization of the Semiannual- Oscillation in Mesospheric Temperatures at Low-latitudes
Advances in Space Research
Novel measurements of the seasonal variability in mesospheric temperature at low-latitudes have been obtained from Maui, Hawaii (20.8°N, 156.2°W) during a 25-month period from October 2001 to January 2004. Independent observations of the OH (6, 2) Meinel band (peak height ∼87 km) and the O2 (0–1) atmospheric band emission (∼94 km) were made using the CEDAR Mesospheric Temperature Mapper. The data revealed a coherent oscillation in emission intensity and rotational temperature with a well-defined periodicity of 181 ± 7 days. The amplitude of this oscillation was determined to be ∼5–6 K in temperature and ∼8–9% in intensity for both the OH and O2 data sets. In addition, a strong asymmetry in the shape of the oscillation was also observed with the spring maximum significantly larger than the fall peak. These data provide new evidence in support of a semi-annual-oscillation in mesospheric temperature (and airglow emission intensities) and help quantify its seasonal characteristics.
Taylor, M.J., A. Taori, D. R. Hatch, H. L. Liu and R. G. Roble, Characterization of the semiannual- oscillation in mesospheric temperatures at low-latitudes, Adv. Space Res., doi:10.1016/j.asr.2005.05.111, 2005.